


Alien Heroine: Izumi

by Angrykarin666



Category: Ben 10 Series, 僕のヒーローアカデミア | Boku no Hero Academia | My Hero Academia
Genre: Adopted Midoriya Izuku, Alternate Universe - Canon Divergence, Crossovers & Fandom Fusions, Family Fluff, Female Midoriya Izuku, Fluff, Gen, M/M, Multi, Other, Pro Hero Ben Tennyson, Quirkless Midoriya Izuku, midoriya izuku raised by others
Language: English
Status: In-Progress
Published: 2020-04-08
Updated: 2020-07-05
Packaged: 2021-03-01 16:35:36
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 4,294
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23550178
Author URL: https://archiveofourown.org/users/Angrykarin666/pseuds/Angrykarin666
Summary: Midoriya Izumi is a quirkless girl, orphaned from the day she was diagnosed as such, who had seemingly unreachable dreams of being a hero. Those dreams turn out to be not as impossible as she thought after she catches the eye of and is adopted by Alien Hero: Ben 10 and his husbands. Being raised away from Earth for the ten years until she can enroll in a hero school leads her growing into a very unusual and different girl then the one that left with the brunette hero.How Will UA and its staff and students handle the daughter of the savior of the Omniverse? And How will Ben and his husbands take to parenting? Read and find out!
Relationships: Albedo/Ben Tennyson, Albedo/Vilgax/Reinrassic III/Ben Tennyson, Ben Tennyson/Vilgax, Reinrassic III/Ben Tennyson
Comments: 57
Kudos: 128





	1. Meeting Izumi

**Author's Note:**

> This story is going to have Ben married to 3 of his past, now redeemed, villains. So if you have a problem with Ben/Vilgax, Ben/Albedo, and Ben/Reiny you might not like this so much. For those still willing to read despite that warning there will be lots of sweet family fluff and cute couple-y interactions between Ben and his husbands. (You all know I love me some fluff and fluffy romance.)
> 
> It also has Izuku as a girl, named Izumi, to balance out the now even more male dominant cast courtesy of adding Ben 10 characters to the story. And sorry, but in this AU Inko was not best mom.
> 
> Now, with that out of the way, let's get to the story!

Ben has been to a lot of schools over the years since his becoming a hero, both human and alien ones, and never gets tired of it. His visits to alien schools are to give some talks about his homeworld and species, maybe explain a bit about being a plumber or pro-hero. But his visits to Earth schools are all about explaining aliens and plumbers to his fellow humans, getting them to know that in the grand scheme of things they aren’t the only people out there.

Nor is heroics exclusively an Earth profession. In fact, it’s through his introduction to plumbers and aliens at these school meet and greets that a vast majority of their newest recruits from Earth come from. It’s nice to know that “Alien Hero: Ben 10” has reignited the long dormant interest to explore the cosmos around the world.

Grandpa Max was especially happy about that, his longevity quirk meaning that he’d lived long enough to see the world change around him since the days before man visited the moon to current day. Seeing the space programs return and the plumbers flush with new, quirked humans just as excited to meet aliens as he was long ago brought a smile to the man’s face. A fact that Ben was very happy about.

If only his Grandfather could be so happy about his marriage…

Shaking off that thought before he can make himself upset the hero of the universe takes a look at the children in the class before him. They’re a bunch of 5 year olds, all wide eyed and vibrating with excitement at the hero in their classroom. This particular class is Japanese, the country Ben visits most often outside the one of his birth on Earth due to it being the heart of modern Earth heroics, and the brunette smiles when he notices a tiny girl in the back with her notebook in hand to jot down notes.

The girl’s mop of curls is a deep green, a style not so far from his own at that age, and her cute round cheeks are dusted with freckles in a way that reminds the hero of one of his husbands. Add in those big green eyes like his own and the focused analytical gaze she’d fixed him in being a mirror of his other husbands’ and it was hard for him not to let out the coo he felt brewing in this chest. That child is exactly what a perfect blend of he and all his spouses would be like.

Shoving that feeling down the Alien Hero beamed and rested his hands on his hips. “Who’s ready to learn about aliens?”

The unanimous hands in the air and excited chatter was a reaction he’d grown used to over the years, but it was still just as pleasant.

His presentation went as it usually did; a brief overview of the plumbers, a very general map of the universe labeling the various territories of space (plumber, various empires, and neutral zones like the Anur System that didn’t really count as either), and a brief explanation of some of the more known species courtesy of the omnitrix. After that he opened the floor for the kids to ask questions, typically getting requests about a particular form he hadn’t explained before with the odd one about himself thrown in there. Most of those about himself were about the rumors of his relationship, many of them being false.

He never got tired of the looks of confusion his marriage got, they were hilarious. Usually immediately followed by questions of “You can be married to more than one person?” or “If you’re married to aliens, what kind are they?”

As usual it was the children who grasped the way his marriage worked the easiest. He and his husbands all liked each other, and could gain more from each other politically and personally if they were married, so they just settled on a polybonding (a bonding or mateship of multiple parties together) to solidify their new alliances. Ben’s marriage was as much a political play as it was a sign of love between him and his partners, that being one of the main reasons his family had so much issue with it in the first place.

…Among other reasons.

The wielder of the omnitrix is pulled from his thoughts as the girl, the same one who caught his eye from the moment he set foot in the room and who he found himself watching throughout his lecture despite himself, raised her hand to ask him a question nervously. “Um… C-can I ask a question?”

Before Ben could respond the teacher, who’d until this point been among one of the better ones the hero has interacted with over the years, spoke in a way that was so flat and harsh it gave the brunette whiplash “I highly doubt you have anything important or interesting to ask him Midoriya. Besides, I’m sure he’s getting tired of answering questions.”

The ensuing tittering from the other children and way the green haired girl curled in on herself had a flame of anger lighting inside the man’s chest. Swallowing it down, but not well enough if the teacher’s flinch at his tone is any indication, Ben says “I believe I’m the one who decides whether a question is worth my time or not. So, ask away miss…?”

“Midoriya Izumi!” the girl introduces herself as, her timid behavior vanishing at the possibility of getting answers. “You said your ability to turn into aliens is part of your omnitrix, and you’ve mentioned before in articles how because of what you’ve learned thanks to that ability that anyone can be a hero if they put their mind to it. So does that mean you believe even a quirkless person could be a hero if they worked hard enough?”

The girl’s teacher snorted and snarked “You would ask a question that stupid despite knowing the answer, wouldn’t you.” her classmates laughing like the spectacled man had told a joke.

“And what, exactly, is wrong with her question?” Ben asked with his green eyes narrowed. The teacher, seemingly oblivious to the alien hero’s ire, continues “Besides the fact that there’s no way a quirkless person could become a sidekick, much less a hero? There’s the fact she thinks ****she’s**** going to be able to be the first quirkless hero.”

Ben changed his mind about this guy, he was an asshole.

Breathing deeply to prevent himself from punching the other man in the face the savior of the universe explains “To answer your question Izumi, can I call you Izumi?” at her nod he continues “It will be hard, harder than it would be for anyone else trying, but it is possible for a quirkless person to be a hero. And as for your teacher’s comments… He is right about one thing, unfortunately. You can’t be the ****first**** quirkless hero.”

The girl’s frown and teacher’s smug look vanished as he finished “Because ** **I**** am already the one holding that particular title. Like you said earlier; my ability to turn into aliens is thanks to the omnitrix, not a quirk. Without it I’m just as quirkless as you are.”

Izumi’s green eyes glittered in awe, a few of her classmates joining her. Because they, like her, had realized what she did. If Ben, a quirkless man, could come to be a hero not just on Earth but across the Universe then it didn’t matter if their quirks weren’t “hero worthy”. Any of them could be a hero too if they tried.

-

As he’d left the school, reporting his distaste of the teacher teaching such blatant quirk discrimination to toddlers to its principal and school board as he did, the brunette had done something impulsive. He had checked Midoriya Izumi’s file. What he’d read inside only left him more tied up emotionally about the tiny child.

For one thing she was an orphan. Not by losing her parents in some tragedy or being given up at birth but by her mother and father straight up abandoning her when she was diagnosed as quirkless. That pissed the hero off to no end.

And on top of that the girl’s records painted her as some kind of brainless delinquent. A fact he could tell was false by her above average vocabulary, active note taking during his lecture, and shy demeanor interacting with other human beings. The girl was a model student, a quiet and smart one, whose teacher was clearly worse than Ben thought at first glance.

Bigotry always had a special place in the shapeshifter’s heart as the thing that pissed him off most.

Sighing and running a hand through his messy brown hair the man made a beeline for his van’s console, pulling up his husbands on a video conference. This was something he needed to run by them first and he really ****really**** hoped they said yes.

“Hello Benjamin, how was the presentation?” came the rich and familiar baritone of Vilgax, who Ben could see eyeing a data pad one of his robot drones had brought up on his left with a grimace. “For the most part it went pretty well, at least until the end when I found out the teacher was a bigot that was teaching his nasty behavior to toddlers. Hopefully that’s been routed before it can take root fully…”

“Ugh… It’s disgusting when teachers can’t at least ****attempt**** at civility and professionalism.” came the tired and flat tone of Albedo, whom Ben smiled at when he noticed the Galvan-turned-human tinkering with something on the call screen. It was always nice knowing that he and their other husbands were the only ones the albino would bother answering a call from when he’s busy.

Speaking of their other husbands; it was here that the third and last of Ben’s husbands chimed in, having taken a moment to think before speaking “Ben-Ben Tennyson, I have noticed you look tenser than usual… Was there something else on your mind?”

It was with that comment that the other two turned their full attention to the call screen, taking in Ben’s appearance far more intently. Well, here goes nothing. “There was something else… something I wanted to do, but thought I should run it by all of you first…”

Three separate sets of red eyes stared at him, their owners motioning wordlessly for him to continue.

“There was a kid here, a little girl, that caught my eye from the moment I stepped in the class. She was cute and taking notes the whole time, but shy… And it was when she asked a question that the teacher revealed how unsuited to teaching he was.”

Albedo smirked teasingly as he quipped “Let me guess, he was biased based on quirks or race and made a comment only towards her due to her being lesser in his eyes because of that. And the moment you knew he was bigoted you put up with precisely none of it and let him and everyone else know that.”

“The former and yes.” the brunette stated proudly before continuing “Anyway. After I answered her question, which was - and I quote - “You said your ability to turn into aliens is part of your omnitrix, and you’ve mentioned before in articles how because of what you’ve learned thanks to that ability that anyone can be a hero if they put their mind to it. So does that mean you believe even a quirkless person could be a hero if they worked hard enough?” Which of course I told her yes, but she’d have to work at it. Though not before her teacher laughed at her and called her stupid to her face.”

The Chimaera Sui Generis smiled fondly before asking “Not that I don’t love hearing this but does this have anything to do with your question or have you gotten off track?”

Green eyes blinked before the hero chuckled “Bit of both. Getting back on track, after that I made sure the school would be dealing with the sad excuse for a teacher and checked on the girl’s file out of curiosity since I was there. First off her teacher had clearly sabotaged her marks, since she’s well above her peers intellectually and was as far from a “disruptive trouble maker who constantly picks fights with other children” as you could get. And second her parents abandoned her last year when she was medically diagnosed as quirkless, so she’s an orphan…”

It was here that all three caught on.

“You want to adopt her?” Reinrassic stated more so than asked, earning a pleading look from his human husband - one which he turned to the other two as well - along with his admission of “I do, I really really do! Can we? Please?”

The Highbreed Supreme mulled the idea over, as did the Warlord, but both were surprised when Albedo was the first to give his approval. “I can already tell you’re set on this, and if your assessment of her is correct then I see nothing wrong with this plan of yours. Perhaps she’ll make a passable lab assistant for me in the future… for a human at least.”

Reiny was the next to agree, noting there were more pros than cons to doing so. And perhaps this was a sign that Ben-Ben was contemplating offspring finally. The Atasian hopes so.

Now all three - Highbreed, Galvan, and Human - were staring at Vilgax with baited breath. The warlord sighs and mutters a resigned “Fine. But if we’re adopting a child she will be raised as a proper heir, and not just to myself.”

Ben squealed with delight as he beamed at his husbands. “I swear if I could I would kiss you right now! I gotta go get this all sorted out, I’ll talk to you again when I’m done! Love you, Bye!” As the brunette ran off to get whatever paperwork was needed to adopt Midoriya Izumi done as quickly as possible his husbands shared a fond look amongst themselves.

“I should be concerned that he has us wrapped around his fingers, but I’m not… Odd as that sounds.” Vilgax muses, earning nods from Reinrassic and Albedo.

“I need to prepare for our new offspring, you two should do the same.”

Albedo rolled his eyes at the Highbreed Supreme “Please, I could prepare her needed study materials for all four of our species’ teaching curricula and optimize it for her in my sleep. I do need to get back to my work though, farewell.”

The pair of rulers shrugged and left to prepare for their new heir separately, Vilgax setting his drones and subjects on preparing rooms for her in both his Warship and his Palace while the Highbreed Supreme sets about doing the same on Augstaka personally.

The child in question meanwhile had no clue how much her life was about to change.


	2. Chapter 2

**Summary for the Chapter:**

> Izumi gets adopted and meets her new family.

Adopting Izumi had been almost disgustingly easy, though considering how obvious it was that the orphanage staff not only didn’t care for her but were eager to be rid of her that wasn’t really a surprise. The green haired girl meanwhile was surprised to see the hero who’d told her the one thing she’d wanted to hear for so long in the “adoption room” as she and the other kids called the meeting room most met their new parents in.

Apparently he and his husbands wanted to be her new parents, the thought made her tear up in joy.

But that was yesterday. Today Izumi was standing next to Ben, her new father, in the lobby of Earth’s Plumber Headquarters. Her bright green eyes scanned the place with awe as she trailed after her hero, holding one of his hands as she mutters observations to herself under her breath.

“Hmm, based off what I can hear of her mumbling your assessment of her intellect seems accurate.” came a tired sounding drawl that cut the child’s mutters off and drew her attention to the speaker. He looked remarkably like Ben, though his hair was white and slightly longer; tied back in a low and short ponytail save for his shorter bangs, which were far tidier then the brunettes. His skin was also paler and his dark ringed eyes a bright red rather than green.

“Izumi this is Albedo, one of my husbands. Albedo this is Izumi, our new daughter.” The plumbers that had been watching them curiously from nearby all gaped at that, one spitting out his coffee in shock.

The albino moved to crouch in front of the green haired girl so he could look her in the eye; his unusual style of dress and lab coat, along with his manner of speaking and less athletic build, had Izumi certain he was a scientist or doctor of some kind here.

“You are correct on both counts, as I am - in fact - one of the leading minds in several fields of study scientifically and medically throughout the Universe. I am Albedo of the Galvan, once apprentice and assistant to First Thinker Azmuth and only being in all of creation besides him capable of building a functioning Omnitrix.”

Oh… Izumi muttered that out loud. The galvan-turned-human’s eyes lit up in amusement “That you did, you really need to break that habit of yours.”

It was here that a clearing throat drew all of their attention and ended the girl’s embarrassment. A group of people stood nearby, some of which Izumi recognized from her hero studies.

There were the three who had been Ben’s hero partners over the years. A red haired woman with magic-like abilities that could only be the Magic Heroine: Lucky Girl, a man with long dark hair and a strong physique clad in dark and striped clothing that was the Adaptive Hero: Kevin 11, and a blue furred cat-like alien who was lithe like Ben was but taller that she knew to be Rook Blonko. She had enjoyed working out the intricacies of his fighting style and all the abilities of his Proto-tool through hours of watching old internet footage of their battles throughout his career on Earth.

A snort of mirth from both of her new parents, as well as Ben rustling her mop of boyish curls affectionately and the trio in question’s impressed and shocked stares at her, led Izumi to realize she was still thinking out loud. “S-sorry.”

The fourth in the group, and the only one the quirkless girl didn’t recognize, was an older man in a Hawaiian shirt with a kind face. “So Ben, who’s the kid with you?”

“Grandpa Max, guys, meet my new daughter Izumi. I just adopted her.” While they gaped the brunette turned his gaze to said daughter “Izumi those are your Great Grandpa Max, Auntie Gwen, Uncle Kevin, and your Uncle Rook.”

“Uncle?” Rook questioned “But I am not-”

“You’re my best friend, you’ve been my partner for years, you’re family in my book.”

-

Ben and Albedo had opted to spend their time waiting for their other husbands to arrive feeding their daughter. Gwen, Kevin, and Rook followed them on the Burger Shack and Mr.Smoothy run - Grandpa Max staying behind for work reasons. Izumi has never eaten chili fries or a smoothie before, a fact Ben had discovered on the trip over here from Japan as they got to know each other better, and the brunette is happy to note she loves both immediately.

It’s shortly after the group have finished eating, all of them sitting around one of the picnic tables near Mr.Smoothy and chatting amiably, that Vilgax and Reiny arrive in one of the former’s small landing ships to pick them up.

Green eyes, much like Ben’s in color but set in Japanese features, scanned the two alien rulers with a critical and curious gaze. Vilgax was the largest of her new parents, both taller and more muscular than even Reinrassic, and had green skin covered in darker green splotches and speckles near the ends of his tentacles. The gaps between his arm tentacles, wound together to resemble humanoid arms, and legs (which may be the same under the armor he wore if the little she could see of them in the small gap that revealed a sliver of his upper thigh was anything to go off of) were a dark red that went well with his solid crimson eyes and red-tinted glass of what looked to be a rebreather attached to his head.

Reinrassic was tall, easily 10 feet in height, with long limbs that faded from the white of his body to a dark black save for the near fully green right arm. His torso had a series of folded, overlapped areas directly below the muscular chest baring four black ringed red eyes set symmetrically in it; contrasting to the four diagonally set smaller ones on his violet face. This alien was the only she saw not wearing clothing of some sort, likely as his species have no need for it, and bore no visible mouth or ears.

Never one able to hold in her thoughts Izumi had, to her parents’ amusement, noted most of her observations out loud in the same clinical way Albedo does his lab projects. The Highbreed Supreme’s eyes narrow in a way that his husbands recognize as smiling (at least the equivalent thereof in Atasian physiology) as he responds to the human girl’s muttered question of “How does his species eat? Do they even need to eat?”

“Atasians organs for transfer of various materials into and out of the body are stored in our torso under these protective flaps of skin and our wings. And our diet is primarily liquid based for ease of consumption.”

Izumi’s awed expression at having one of her questions answered is as cute as it is sad. How anyone can be cruel to a child this cute and intelligent baffles everyone else present. Ben takes comfort in the fact that their daughter won’t have to deal with that anymore, not if he and his husbands have anything to say about it.

Picking up the green haired girl the Alien Hero turns to wave goodbye to his cousin, best friend, and partner with a smile. “See you guys later! We should get going if we plan to keep on schedule.”

“Bye bye!” Izumi called with a wave as she and her fathers board the ship in the parking lot and fly up to the Chimaeran Hammer waiting just beyond Earth and the moon’s orbits.

The Galvan-in-human-form turned to address his husbands as they walked down the halls to the control room of the warship “So what pray tell is our schedule?”

Vilgax, sitting down in the throne-like captain’s seat and pressing a few buttons on it to get them moving, answers “We are staying in Vilgaxia for a week, introducing our heiress to her subjects there and starting her lessons as Princess to my empire.”

Reiny then added “Then we will go to Augstaka to do the same for my own people, who have been quite excited to hear they have an heir from me. Highbreed Supreme is a title that passes through blood lines, though our race’s difficulty breeding before Ben-Ben healed our genetic damage led to the title passing to to me as the one considered most pure in breeding and ideals.”

It is here the Izumi realizes something, having remained quiet to absorb the information she’d noted and learned about her parents so far. Shocked, she asks in open disbelief “Wait… I’m a princess now?!”

Ben beams down at her “Twice over, thrice if you count my title - which most aliens do. Bearer of the Omnitrix and Savior of the Universe are titles that put me on par with or above royalty on its own, my marrying the rulers of two of the largest Galactic Empires really only solidified that.”

Shoving that tidbit of knowledge to be processed later Izumi asks another question that had been on her mind for a while “What do I call all of you? I can’t call all of you dad, since that’d get confusing, and I don’t really feel comfortable referring to my parents by name.”

Reinrassic cocks his head, explaining “All Atasians are capable of both siring and carrying offspring. We call the parent who births us our Dam and the one who sires us our Sire, you may call me whichever you deem preferable.”

After a moment the human girl decides “I’ll go with Sire.” earning a rumbling purr from the Highbreed.

Albedo shrugs. “Galvan rarely raise their own offspring, usually growing up in communal hatcheries and apprenticing under whatever master we catch the eye of through our studies in the Academy upon leaving adolescence and our tails behind. You may call me whatever you wish.”

Ben is Dad already, having claimed the English title himself upon adopting her, so Izumi goes with the more familiar to her “Otou-san” for the scientist.

Vilgax immediately declares his own preference once the others are done, stating “As my heiress it would be best if you called me Father, anything less formal would be frowned upon for those of our status.”

“Okay.”

After a brief moment of silence Albedo holds his arms out and tells Ben “It’s best if I get started on her lessons now, so she won’t be running completely blind on Vilgaxia or Augstaka.”

Transferring the green haired girl over to the galvan’s arms the brunette ruffles her hair. “Have fun kiddo, Al’s got a lot to teach and I think you’ll like the challenge.”

Given the way her green eyes sparkled at the idea of learning from the genius Ben was probably right.

**Notes for the Chapter:**

> Hope you guys liked this so far. Next chapter should have the visits to each parent's homeworld (Including Galvan Prime and excluding Earth for obvious reasons) and adapting to her new life and status.


End file.
